Pulverizing apparatus



' 1,641,445 P 1927' w. J. A. LONDON PULVERIZING APPARATUS Filed Jan; 28.1925 e sheets-sheet 1 INVENTOH 7 BY WZ/ZNEYG 6 Sheets- Sheet 2 FiledJan. 28,1925 1 fang?? I By Sept. 6,1927. ,4 5 7 W.. J. A. LONDON PULVERIZ ING APPARATUS Filed Jan. 28. 1-925 6 Sheets-Sheet 5 NI/E/VTOR WfMaATTORNEYS Sept. 6, 1927.

w. J. A/LONDON PULYERIZING APPARATUS Filed Jan. 28. 1925 6 Sheets-Sheet4 I Z7 I Ami/ Er 1 Sept. 6, 1927. 1,641,445 W. J. A. LONDON PULVERI ZING APPARATUS Filed Jan. 28, 1925 6 Sheets-Sheet 5 L 2 J ATTORNEYS Sept.6, 1927. 1,641,445

w. J. A. LONDON PULVERIZING APPARATUS Filed Jan, 1925 6 Sheets-Shet 6 am m 7 m 1N V m M 0 xx 1 .l/ J l 1 0 v fl d f a 6 6 w d 0 z 2 Z 4% Y Z i.1 Aw\w\\ r V// Patented septa 6, 19 27.

UNITED STATES PATENT OFFICE.

WILLIAM if. A. LONDON, OF HARTFORD, CONNECTICUT, A'SSIGNORTOINTERNATIONAL COMBUSTION ENGINEERING CORPORATION, A CORPORATION OFDELAWARE.

' PULVERIZING APPARATUS.

Application fi1ed .Tanuary 28, 1925. Serial No. 5,193.

This invention relates to pulverizing apparatus and more particularlyfor pulverizing coal for burning in powdered form.

The object of the presentinvention is to provide a pulverizer which iseffective for its intended purpose and which is relatively simple inconstruction and the interior. parts of which are readily] accessiblefor renewal and 'repair.. In a pulverizer constructed according to thisinvention the rotary portions thereof including the impeller canberemoved as a whole in a comparatively short time-and any worn partsthereof readily replaced.

The above and other'advantages can be realized by the constructionhereinafter more particularly described andclaimed.

The accompanying drawings illustrate by way of example one embodiment ofthis invention and in these drawings:

Fig. 1 is a front elevation, partly in section of a double type ofpulverizer. n

Fig. 2 is a side elevation of the pulverizer in part section.

Fig. 3 is a front sectional elevation corresponding to Fig. 1 throughpart of the pul-' verizer. 4

Fig. 4 is a transverse sectional view of the pulverizer takensubstantially 0n the line -4-4 of Fig. 1 with the rotary impellerremoved.

-Fig. 5 is a partial side view of the mpeller shown in Fig. 1, on alarger scale and in part section.

" this application. Inorder to obviate exces- Fig. 6 1s a crosssectional view taken on the line 6 6 of Fig. 5.

Fig. 7 is a sectional view taken on the line 7-7 of Fig. 2.

The apparatus here illustrated is adapted to form part of a pulverizingsystem such as-set forth in the U. S. application of John E. Bell,Serial No.- 625,193, filed March 15th,,1923, and assigned to theassignee of sive expenditure of power, air is admitted to thepulverizing apparatus only in limited amounts, preferably not exceedingmaterially the minimum required for the handling of the pulverizedproduct. When the pulverizer is operated as hereinafter indicated, theair may be limited to from 50 to' 100 per centlof the fuel by'weightrFor this purpose, a suflicient depth of coal to act as a partial sealmay .be maintained in the supply bin, and the area of the supply conduitor feeder casing may also be appropriately limited.

Referring to the drawings, the apparatus comprises what may be somewhatloosely termed a centrifugal rotary impeller 1 with blades 2 for actingon the coal. ,The impeller is mounted on a shaft 3 that revolvesinsuitablymounted bearing structures .or

pedestals 4 and is driven by any suitable means not shown. The impeller1 is enclosed in a casing \or housing divided in halves 5 and 6 forconvenience in assembling the machine or opening it up. In theconstruction illustrated the housing is divided diametrically at 5 sothat the portion or cover 6 may be turned on a pivot or" shaft 7 mountedupon the fixed portion of the housing. The adjoining portions of thecasing along the line5 are provided with flanges 8 formed with recessesfor thereception of bolts 9 whereby the cover 6 is se- The housing isalso divided vertically and each divided portion is formed with a flange5 having holes 5 forthe reception of bolts (not shown) whereby thehousing is secured together vertically. It will be seen'thereforethat-each of the portions 5 and 6 of the housing are formed of' twoparts bolted together through the flanges 5".

The cover 6 is provided on each side thereof with a laterally projectingarm 10 from which is suspended a slotted link 11 connecting the said armwith a cap 12 mounted upon the bearing structures or pedestals 4 whichsupport the impeller shaft 3. The link 11 on the left hand side as,viewed in Fig. 1 is attached to a yoke 13;which connects the cap 12 witha cap 14 mounted upon a support for a thrust bearing 15 so that ashereinafter described, the two caps 12,12 and the cap 14 can all beraised together.

The bearing structures or pedestals 4 are supported upon box-likestructures 16 projecting from either side of the casing and formedintegral therewith as shown in Fig.

cured to the fixed portion of the housing.

cooling coil 19 is provided for keeping the lubricant cool.

Crushed coal to be pulverized is supplied to the impeller 1 from eithersidethrough intakes 19 to which the coal is conveyed from a hopper 20 byscrew conveyors 21 driven by a motor 22 through pulleys 23 and belts 24.The discharge outlet 25 of each intake communicates with a chute ordcE-flector 26 which causes the coal to flow into the impeller 1 whence thecoal is discharged peripherally into a surrounding annular receivingchamber 27. This chamber has a discharge outlet 28 at its bottom andincreases inicross-section, by gradual enlargement both laterally andradially, either way' around from top to bottom. That is to say theimpeller axis is substantially above the centers of the casing 5 and thechamber 27. In the path of the discharge from the impeller outward intothe chamber are impact surfaces for shattering any doal lumps that mayreach them, "afforded by members 29 mounted in the casing 5. In the.construction illustrated the members extend across a relatively narrowannular throat 30 between the impeller periphery and the ans nularchamber. The members 29 are in the form of rectangular plates thin incross-section compared with their length and breadth and are held inslots 31 formed in liners 32 secured to the Walls of the casiiig 5* onthe inner faces thereof. These liners; are provided for the purpose oftaking up wear and are readily renewable. They are annular' in form ofthe cross-section shown in Figs. 1 and 3, with a concave 33 adjacentthecasing 5 and a convex surface 34 on the impeller side. the two linersthus forming the throat 30 through which the coal is discharged. Theslots'31 for the reception of the members 29 are formed in thisprojectingpprtion of the vannular liners and it will be 0 served'thatthe slots are greater in X length than thewidth of the members, thusfacilitating the removal of the latter for renewal. Each member is heldin position by a pair of set-screws 34, 35 at each end one of whichset-screws (34) has a pointed end 36 which enters a correspondinglyshaped recess 37 in the end of the member 29 but this recess has itsaxis eccentric to the axis of the set-screw, as shown more clearly inFig. 3, so as to provide an inclined plane against which the end of theset-screw bears. with the result that when the set-screws 34 areadvanced the member 29 is seated on and forced against the outer edgesof the slots 31. I The member 29 is then further held againstlongitudinal movement by the other set-screws 35 which are butt-ended tobear against the ends of the member 29. These set-screws 34, 35 arepassed through screwthreaded holes 38in the walls of the housing 5 andareprovided ,vith lock-nuts 39 for memes holding themin the positions towhich they have been adjusted. 2

' The impeller. 1 comprises a radially tapering disc 40 mounted fastupon the shaft 3 and disposed centrally between two annular discs 41, 41which are so shaped as to form on either side of the central disc anopening 42. for the admission of coal tothe central intake pace in theinterior of the impeller 1, and diverging outlets '43 through Whichthecoal is discharged. The impeller "is provided with blades 2 as best Seenin Figs. 5 and 6 each of which is tapered to correspond with thediverging outlet 43 and is formed on one face with a recess 2 while itslongitudinal: edges are formed with flan'ges'2. Thev tapered disc 40'isformed with tapered extensions .44 disposed on opposite sides thereofvand integral therewith. s A blade 2 is mounted on eaph of these'extesions by engaging the recessed portion 2 thereof with one side of thesaid extension and then the blade is secured to the extension by a stud45 which is passed through an in-' clined hole 46in the extension theend of the W stud beingscrew threaded to engage a screwthreaded hole inthe blade. The studs 45 merelyserve to support the blades and are notsubiected to any stress during the rotation of the impeller. Eachextension 44 has also formed in the free outer edge'thereof a slot 47 toreceive the head of the stud. The outer'ends of the extensions 44 entercor; responding recesses 48 in the annular discs 41. and the impellerdisc and annular discs nu thus assembled are permanently securedtogether by rivets 49.

In order to take up wear and to protect the faces of the central disc 40and the annulafdiscs 44 where same form the outlets from the impellerthese'faces are provided with wearing plates 50 of the shape bestshownin Fig. 5 which platesare interposed between the extensions 44.Each plate has the edge adjacent to the oneextension con- 1 10 vex fromtheinner periphery to the extension, then recessed'as at 51 to receiveone edge of the extension 44 and has a straight edge 52 whichabutsagainst the said exten-.

sion. Theopposite edge of the"plate 50 has 5 a portion concave from theinn-er periphery to the extension, a recessed portion 53 to receive theedge of the extension next in order, a curved portion 54 which surroundsthe lat-i ter extension and a straight portion 55 which abuts againstthe wearing plate next in order. In this manner. the seyeral Wearingplates snugly engage the onewith the other and when .it is desired toremove any one of these plates the adjacent blades 2 are first 1-25removed by Edetaching their studs 45 and withdrawing the blades, theplate 50 is then i moved along the extension until it is over the slot47 in the latter. This plate will nowbe in aposition with its curvedportion 54 over the slot 47. whereupon the plate is turned, whichturning is permitted by the curved portion 54 of the plate passingthrough the slot 47 in one extension 44 while theconvex edge of theplate passes the op posing face of the adjacent extension. The platesare composed of wear resisting material such as manganese steel and theblades are also preferably composed of similar material.

As previously stated the coal to be pulverized is supplied laterallythrough the intakes 19. .Each of these intakes together wvit-h itsconveyor 21 is a separate part divided verticallythrough the hopper 20.The outlet from the intake 19 discharges into the chute or deflector 26which is of the form the housing 5 and the chute or deflector'26 isinserted therein by raising the cover 6 of the housing, engaging theridge 26f with the shown in Figs. 1, 3 and 4 and has an inclined surface26 tending to deflect the coal into the opening 42 of the impeller. Thedefleeting surface extends from a vertical arcuateflange or support 26having a curved ridge or rib 26 for engaging a correspondingly shapedgroove 26 in the housing. The groove 26 is formed in the fixed portionof groove and moving the deflector along'the groove until it reaches astop fixed to the housing. When the cover 6 is again closed -a stop 56thereon holds the chute inposithe portion 58 and the shaft 3. 'The guardis also provided with an arcdate plate 60- adaptedto engage the cover 6and guide it into place, when the cover is lowered into position. Thisplate 60 ensures. proper registry of the two portions of the impellercasing.

g The annular discs 41 of the impeller are provided with hollowtrunnions 61 which work in bearings supported upon rings 62 mounted inthe walls of the housing as best shown in Fig. 3.

- The portion or cover 6 of'the housingis 7 provided on each side wallwith a hook 63 pivotally mounted thereon in a plane above. the plane ofthesli'aft- 3 andpreferably in alignment with the centre of the shaft;the free end of the hook being supported when not required for useupon asupport 64 projecting from the wall of the cover 6. The

front wall of the cover is provided with two flanges 65 and to each ofthese flanges are attached, below the axis of the shaft 3, the

lower ends of a pair of links 66" the upper ends of which are connectedby a shaft 67 with the corresponding pair of links-on the other flangeof the cover. Upon the shaft 67 is mounted a yoke 68 whereby) the cover6 may be, raised by anysuita le means. LWhen' it is desired to removethe impeller 01 thebolts 9 connecting the two portions of the housingand the bolts retaining the bearing caps 12, 12 and 14 are first takenour. The cover 6 is then raised by pulling the yoke'68 upward with theresult that during the first part of the upward movementof theroverabout its pivot 7 the laterally extend:

ing arms 10 thereon will lift the caps 14, 12, 12 of the bearings 15, 4,4, same being effected by reason ofthe links 11 which connect the arms10 to, said caps. When the cover 6 has been raised sufliciently thehooks 63 are swung clear of the supports 64 and into engagement with theimpeller shaft 3 so that on further movement ofth'e cover the shaft willbe raised from its bearings. The impeller and shaft '3 can now bereadily removed on a suitable truck and another impeller placed. inposition;

The casing; may ,be provided with one or more peripheral manholes 69 orother open-' ings affording convenient access to the chamber 27 andthese openings may be closed by covers 70 having their inner surfacescurved in conformity with the interior of the casing.

In the operation of the pulverizer the 1mpeller may be rotated at auniform peripheral speed as high as about 36000 feet per minute, withthe result that a high velocity is imparted to the air entering theapparatus and cohsequently a suction is created suflicient to draw thecoal from the intakes to the central openings of the impeller. At

this point the coal lumpstend to spreadannularly and to pass toward theblades,

almosta thousand of whichpass agiven point in a second. The'number andarrangement of the blades 2 is such that the-delivery a d discharge ofcoal to and from them is ubstantially uniform.- .The coal is reduced bythe blades and the producttis discharged from the impeller at a highlinear velocity to strike the impact members '29 -with the resultthat'if there are any pieces not reduced, these are shattered andreduced I to a suitable degree of fineness.

What I claimis: 1. A pulverizer comprising a rotary 1mpeller and a shafttherefor. a casing for said impeller comprising portions separable atsaid shaft, and an annular guard around said shaftwithin tliecasing,removable with the shaft when the casing is opened.

4 2. A pulverizer comprising a rotary. impeller and a shaft therefor, acasing for said impeller comprising hinged portions divided so as toopen at said shaft, an annular guard around said shaft within the r p iH O I casing, and means on said guard for 1118111- said shaft, and asupply chute for said inn-- peller beneath the shaft engaged with alower casing portion and held in place therein by an upper one whenclosed, but released for removal when such upper portion is openedw A 4.A centrifugal pulverizer comprising an impeller disc, a shaft on whichsaid disc -is mounted, a casing for said impeller divided into twoportions one of which is pivoted to the other, bearings supporting saidshaft, covers for said bearings and means connecting the pivoted portionofthe casin to said covers whereby the covers for said earings areraisedsimultaneously with the raising-of the pivoted portion of thecasing.

5. A pulverizer comprising a centrifugal impeller, a casing for theimpeller divided into two portions pivoted the one to the other, anannular throat in said casing, a receiving chamber into which saldthroat .opens, a serles of impact members in said casing.

mounted in said openings. Q

i 8. A pulverizer impeller comprising a centhroat in the pathof the.discharge therefrom outward into said receiving chamber, and

the

6. A pulverizer impeller comprising discs spaced apart, a discintermediate the spaced discs and forming therewith outlet passagesmeans for raising the pivoted portion of which diverge outwardly, anddetachable blades interposed between the centraldisc and the outerdiscs.

i 75 Apulverizer impeller comprising a central tapered disc discs oneither side thereof and spaced therefrdm'to provideopenings divergingoutwardly, and detachable blades tral disc, discs on either side thereofand spaced therefrom to provide'outlet passages, wlateral extenslons oneither side of the central disc and abutting against the outer discs,

and blades detachably mounted on said extensions. i 4 v 9. A pulverizerimpeller comprising a cen tral disc, discs on either side thereof andspaced therefrom to provide outlet passages,

a series of lateral extensions on either side. of the central disc andwithinsaid passages, blades detachably securedto. said extensions,

-and removable face-plates mounted on said dISCS within the saidpassages.

.10, A pulverizer having an mlieller comprising a central disc, discs oneither side thereof and spaced therefrom to provide outlet passages,andblades detachably mounted in said passages in combination withacasing enclosing said impeller, said casmg having an annular restrictedportion mg a nearest forming a throat aro,und said impeller and a seriesof impact members in said throat 11. A pulverizer having an impellercomprising a central disc, discs on either side,

thereof and spaced therefrom toprovide outlet passagesiand bladesdetachably mounted in said passages, in combination with a having anannular restricted po tion form-u said passages, a casing enclosing saidimpeller discs. annular; liners in said casing forming a throat aroundsaid impeller, and a series of impact members in said throat. 13.111 apulverizer the combination of a centrifugal impeller disc, discs oneither side thereof and spaced therefrom to provide outlet passages,blades detachably mounted,

in said passages, a casing enclosing said impeller dISCS, annularconcavo convex liners in said casmg formlng a throat around saidimpeller, and a series of impact members in said throat. o

- 1% A pulverizer comprising a centrifugal impeller, a shaft on whichsaid impeller is mounted, a casing for the impeller divided into twoportions pivoted the one to the other, an outlet from saidcasing anannular throat in said casing, a receiving chamber into which saidthroat opens and increasing let,\a series of impact members in saidthroat in thepath outward into said receiving chamber, means, forraising the pivoted portion of the 'casingyan annular guard carried bythe casing and embracing the impeller shaft and means on said guard forensuring proper registry'of the casing parts when said parts arebroughttogether.

" cross section from its top around to said out- 15. A pulverizercomprising in combinareceiving chamber into which said throat opens andincreasing in cross section from its top around to said outlet, a seriesof impact members in said throat in the pathQoutward into said receivingchamber, means for-raising thevpivoted portion of the cas ing, anannular guard carried by the casing and embracing the impeller shaft,and a dowel on said gifard for ensuring proper tion a centrifugalimpeller, a shaft on which I registry of the casing parts when saidparts are brought together.

16.- A pulverizer comprising in combination a centrifugal impeller,a,shaft on which said impeller is mounted, a casing for the impellerdivided into two portions pivoted the one to the other, an outlet fromsaid casing, an annular throat in said casing, a receiving chamber intowhich said throat opens and increasing in cross section from its toparound to said outlet, a series of ,impact members in said throat in thepath -divided into two portions one of which is pivoted to the other,bearings supporting 4 said shaft, covers, for said bearings, meansconnecting the pivoted portion of the casing to said covers, meansconnecting the pivoted portion of the casing to the shaft and means forraising the pivoted portion of the casing and simultaneously raising thecaps on the bearings and the impeller and impeller shaft from itsbearings.

18. A centrifugal pulverizer comprising in combination an impeller, ashafton which said impeller is-mounted, a casing for said impellerdivided into two portions one of which is pivoted to the other, meansfor raising the pivoted portion of the cover, an areuate chute'ylocatedin the stationary portion of the casing to partially embrace theimpeller shaft and removable from said casing when the pivoted portionthereof is raised. v

19. .A centrifugal pulverizer comprising in combination an impellerdisc, impeller blades detachably carried thereby, a shaft for saidimpeller, a casing enclosing said disc and blades and divided into twoportions pivoted the one to the other, means for raising the pivotedportion of the easing, an annular guard surrounding the impeller shaft,an arcuate chute partially surrounding said shaft outside the annular,

guard, means on the respective portions of the casing for retaining saidarcuate chute in position and permitting of the removal thereof when thepivoted portion of the casing is raised.

20. A centrifugal pulverizer comprising.

in combination an impeller disc, impeller blades detachably carriedthereby, a shaft for said impeller, a casing enclosing said disc andblades and divided into two portions pivoted the one to the other, meansfor raising the pivoted portion of the casing, an annular guardsurrounding the impeller shaft, an arcuate chute partially surroundingsaid shaft outside the annular guard, and stops on the respectiveportions of the casing for retaining said arcuate chute in position andpermitting of the removal thereof when the pivoted portion of the casingis raised.

In testimony whereof, I have hereunto signed my name.

WI-LLIAM J. A. LONDON.

